Characteristics of Boron Doped Mesophase Pitch-Based Carbon Fibers as Anode Materials for Lithium Secondary Cells

AbstractMesophase pitch-based Carbon Fibers(MCF) have been investigated as anode materials for lithium secondary cells by examining their physical and electrochemical properties. Discharge capacity and initial charge-discharge efficiency of the materials were studied in relation to the heat treatment temperatures of MCF. MCF heat treated at about 3,000° C gave high discharge capacity over 310mAh/g, good efficiency (93 %) and superior current capability of 600mA/g (6mA/cm2). On the other hand, to improve the battery capacity, Boron was doped to the fiber about several % by adding B4C to the pre-carbonized milled fibers and then heat-treated up to 3000°C in Ar. Then heat treated at 2,500°C under vacuum condition to remove remained B 4 C. The structure of Boron-doped fibers was characterized and compared with that of non-doped standard fibers, and also Li ion battery performances are evaluated. The Boron-doped MCF indicated improvement in graphitization and increased discharge capacity as high as 360mAh/g. The voltammograms of both fibers are different from each other. The cell mechanism is discussed based on the unique structure of Boron-doping to the MCF is very effective for the battery performance.

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Characteristics of Mesophase Pitch-Based Carbon Fibers as Anode Materials for Lithium Secondary Cells

MRS Proceedings ◽

10.1557/proc-393-357 ◽

1995 ◽

Vol 393 ◽

Cited By ~ 2

Author(s):

Toshio Tamaki

Keyword(s):

Carbon Fiber ◽

Electrochemical Properties ◽

Carbon Fibers ◽

Discharge Capacity ◽

Anode Materials ◽

Mesophase Pitch ◽

Good Efficiency ◽

Heat Treated ◽

Initial Charge ◽

Discharge Efficiency

ABSTRACTMesophase pitch-based Carbon Fibers(MPCF) have been investigated as anode materials for lithium secondary cells by examining their physical and electrochemical properties. Discharge capacity and initial charge-discharge efficiency of the materials were studied in relation to the heat treatment temperatures of MPCF. Carbon fiber which was heat treated at about 3,000’C gave the highest discharge capacity(over 300mAh/g), good efficiency (92%) and superior current capability (600mA/g). Carbon fiber heat treated at less than 1,000·C, also has superior discharge capacity(over 500mAh/g) at the first cycle, however efficiency was relatively low. Some of the relationships between structure of MPCF and electrochemical properties are discussed below.

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Structures and physical properties of carbon fibers from coal tar mesophase pitch

Journal of Materials Research ◽

10.1557/jmr.1987.0850 ◽

1987 ◽

Vol 2 (6) ◽

pp. 850-857 ◽

Cited By ~ 61

Author(s):

T. Hamada ◽

T. Nishida ◽

Y. Sajiki ◽

M. Matsumoto ◽

M. Endo

Keyword(s):

Heat Treatment ◽

Carbon Fibers ◽

Coal Tar ◽

Transverse Cross Section ◽

Mesophase Pitch ◽

X Ray Diffraction ◽

X Ray ◽

Transverse Magnetoresistance ◽

Heat Treated ◽

Degree Of Graphitization

Carbon fibers having various types of structures were prepared by spinning coal tar mesophase pitch, followed by thermosetting and heat treatment at high temperature. Two kinds of spinning—spinning with stirring the pitch above a capillary and without stirring—have been tried to form pitch fibers from coal tar mesophase pitch. Carbon fibers obtained from mesophase pitch and spun without stirring have a radial transverse structure where the graphite layers are arranged radially in the transverse cross section of the fibers. Carbon fibers made with a stirring system can have random, onion, and a novel “quasionion structure” by changing the spinning conditions. Carbon fibers spun with stirring are less graphitizable than those spun without stirring. No separation of the ten diffraction bands into 100 and 101 peaks and no appearance of a 112 peak were observed by x-ray diffraction when the fibers were heat treated at 2700°C, whereas carbon fibers spun without stirring show clear evidence of graphitization by heat treatment at 2700°C. Transverse magnetoresistance effects at 77 K, (Δρ/ρ)t have been measured to characterize the structure of the carbon fibers. The carbon fibers spun with stirring and heat treated at 2500°C generally exhibit a negative transverse magnetoresistance effect, whereas the carbon fibers spun without stirring exhibit a positive magnetoresistance. Good correlations are found among d002, Lc (002), transverse magnetoresistance, and resistivity at room temperature of carbon fibers spun under various conditions and heat treated at 2500°C. The tensile strengths (TS) of carbon fibers that are less graphitized are higher than those of carbon fibers with a higher degree of graphitization if tensile moduli (TM) are almost constant.

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Preparation and Electrochemical Properties of LiMn2O4 Nanofibers via Electrospinning for Lithium Ion Batteries

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.799 ◽

2012 ◽

Vol 562-564 ◽

pp. 799-802 ◽

Cited By ~ 1

Author(s):

Shuai Liu ◽

Yun Ze Long ◽

Hong Di Zhang ◽

Bin Sun ◽

Cheng Chun Tang ◽

...

Keyword(s):

Discharge Capacity ◽

Lithium Ion ◽

Average Diameter ◽

Potential Range ◽

Charge Capacity ◽

High Discharge ◽

High Discharge Capacity ◽

Initial Charge ◽

Charge Discharge ◽

Scanning Electron

LiMn2O4 nanofibers were prepared via electrospinning and followed by calcination. The surface morphology of as-spun and pure LiMn2O4 nanofibers was characterized by a scanning electron microscope (SEM) with an average diameter of 180 nm. After calcination at 800 °C in air for 5 h, charge/discharge capacity of pure LiMn2O4 nanofibers was measured in the potential range of 3.0 to 4.3 V. Battery testing showed that LiMn2O4 have a high discharge capacity of 80 mAh/g and 85% of the initial charge capacity was maintained for 5 cycles.

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Nanostructured WSe2/C composites as anode materials for sodium-ion batteries

RSC Advances ◽

10.1039/c5ra25645c ◽

2016 ◽

Vol 6 (16) ◽

pp. 12726-12729 ◽

Cited By ~ 35

Author(s):

Zhian Zhang ◽

Xing Yang ◽

Yun Fu

Keyword(s):

Solid State ◽

Discharge Capacity ◽

Solid State Reaction ◽

Anode Materials ◽

Carbon Matrix ◽

Sodium Ion ◽

Sodium Ion Batteries ◽

High Discharge ◽

High Discharge Capacity ◽

Excellent Cycling Stability

75.57% crystal WSe2 nanoparticles are uniformly dispersed on a carbon matrix to form WSe2/C nanomaterials using a solid-state reaction. The WSe2/C nanomaterials in sodium-ion batteries exhibit high discharge capacity and excellent cycling stability.

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Connecting carbon nanotubes to polyoxometalate clusters for engineering high-performance anode materials

Physical Chemistry Chemical Physics ◽

10.1039/c4cp03202k ◽

2014 ◽

Vol 16 (36) ◽

pp. 19668-19673 ◽

Cited By ~ 40

Author(s):

Wei Chen ◽

Lujiang Huang ◽

Jun Hu ◽

Tengfei Li ◽

Feifei Jia ◽

...

Keyword(s):

Carbon Nanotubes ◽

Electronic Properties ◽

Discharge Capacity ◽

Anode Materials ◽

High Performance ◽

Covalent Modification ◽

Capacity Retention ◽

High Discharge ◽

High Discharge Capacity ◽

Structural And Electronic Properties

Carbon nanotubes (CNTs) possess excellent structural and electronic properties and have been widely investigated as anode materials. Covalent modification of carbon nanotubes (CNTs) with organosilica-containing polyoxometalate (POM) leads to the formation of the nanocomposite CNTs–SiW11 with high discharge capacity, good capacity retention and cycling stability.

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Co-construction of sulfur vacancies and carbon confinement in V5S8/CNFs to induce an ultra-stable performance for half/full sodium-ion and potassium-ion batteries

Nanoscale ◽

10.1039/d0nr08788b ◽

2021 ◽

Author(s):

Lihong Xu ◽

Xiaochuan Chen ◽

Wenti Guo ◽

Lingxing Zeng ◽

Tao Yang ◽

...

Keyword(s):

Carbon Fibers ◽

Anode Materials ◽

High Energy ◽

Potassium Ion ◽

Sodium Ion ◽

Sodium Ion Batteries ◽

Vanadium Sulfide ◽

Stable Performance

To construct anode materials for sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs) with high energy, and long lifespan is significant and still challenging. Here, sulfur-defective vanadium sulfide/carbon fibers composite (D-V5S8/CNFs)...

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dual-ion charge-discharge behaviors of Na-NiNc and NiNc-NiNc batteries

Materials Advances ◽

10.1039/d1ma00007a ◽

2021 ◽

Author(s):

Jinkwang Hwang ◽

Rika Hagiwara ◽

Hiroshi Shinokubo ◽

Ji-Young Shin

Keyword(s):

Discharge Capacity ◽

Electrode Material ◽

High Stability ◽

Coulombic Efficiency ◽

Active Electrode ◽

High Discharge ◽

High Discharge Capacity ◽

Charge Discharge ◽

High Coulombic Efficiency

Dual-ion sodium-organic secondary batteries were provided with antiaromatic porphyrinoid, NiNc as an active electrode material, which implemented inherent charge-discharge behaviors with high discharge capacity, high stability, high Coulombic efficiency with...

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Metal-insulator transition in highly disordered carbon fibers

Journal of Materials Research ◽

10.1557/jmr.1992.0940 ◽

1992 ◽

Vol 7 (4) ◽

pp. 940-945 ◽

Cited By ~ 23

Author(s):

K. Kuriyama ◽

M.S. Dresselhaus

Keyword(s):

Carbon Fibers ◽

Structural Changes ◽

Dark Conductivity ◽

Activated Carbon Fibers ◽

X Ray Diffraction ◽

Metal Insulator ◽

Heat Treated ◽

Insulator Metal Transition ◽

Disordered Carbon ◽

Diffraction Patterns

The electronic transition from localized to delocalized states of carriers in a disordered carbon material is investigated by photoconductivity measurements. Phenol-derived activated carbon fibers, where the carriers are strongly localized due to disorder, are heat treated in the range 300–2500 °C to give rise to the insulator-metal transition. Dark conductivity, Raman spectra, and x-ray diffraction patterns are also measured to characterize their structural changes. As a result, the transition temperature was determined to be rather low, around 1000 °C, considering the rapid decrease in the photoconductivity above this temperature. This decrease was ascribed to a fast recombination between the photoexcited carriers and the delocalized carriers generated by heat treatment.

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